索引词：expatiate
例文：[例1] And now the public being invited to the purchase of minor objects, it happened that the orator on the table was expatiating on the merits of a picture, which he sought to recommend to his audience: it was by no means so select or numerous a company as had attended the previous days of the auction. 眼前出卖的都是些次要的货色。桌子上面的演说家正在把一张图画推荐给各位买客，一味地称扬它的好处。那天到的人很杂，也远不如前几天拥挤。 注意动词expatiate后面搭配的介词是“on/upon”。